Successful topical treatment of oral lichen planus and leukoplakias with fenretinide (4-HPR).

Eight patients with diffuse (non-operable) pre-cancerous lesions (oral lichen or leukoplakias) were treated with fenretinidec (4-HPR) applied topically twice daily. After one month of therapy two patients had complete remission and the other six had a greater than 75% response. 4-HPR was well tolerated, and no local or distant side effects were observed. Topical treatment may be combined with oral administration at lower doses to obtain therapeutic results with less toxicity than observed with oral administration alone. A study to further evaluate the efficacy of topical treatment is in progress at our institute.